1. Field of Invention
This invention relates to hardware for the mounting of a water unit to a printing press, more particularly, mounting hardware for the mounting of a Varn Kompac.COPYRGT. automatic dampening system to a Chief 15 or 17 printing press manufactured by American Type Founders (ATF).
2. Description of Prior Art
Maintenance of the proper ink-water balance presents the most difficult task to operators of offset printing presses. This problem accounts for most of the stock and ink waste, down-time, and the general loss of quality that drains profits.
Standard small offset printing presses generally operate as follows: A paper (called stock) feeding mechanism delivers the blank stock to an assembly of rollers, one of which has the plate holding the image which is to be transferred to the stock.
The offset process requires three cylinders for production. The plate cylinder has a relatively thin zinc or aluminum prepared printing plate fastened tightly around its circumference. Super-imposed around this plate cylinder are the inking and watering, mechanisms. The plate cylinder does not come in contact with the paper or other material to be printed; instead, the plate cylinder impresses an image on an intermediate cylinder around which is affixed a specially composed smooth rubber blanket. The rubber blanket, having received the impression, in turn transfers or offsets it onto the paper or other material while it is being carried around the actual impression cylinder, rotating in juxtaposition to the first two cylinders.
In lithographic offset printing, the image on the plate retains ink as it passes by the inking unit, but is insoluble to water as it passes by the water unit. The non-image areas of the plate are not so treated and are wiped clean with water from the water unit. These wiped off areas then become the blank areas of the stock.
Conventional water units for small offset printing presses have a number of rollers, some with absorbent covers called "molletons" which serve to take water and apply it to the plate. Severe problems exist with conventional water units, however, in that the maintenance of the proper ink-water balance is extremely difficult.
Not only must this balance be monitored closely and constantly adjusted by the operator, but also, the very nature of the equipment produces water drips upon stock and often creates dirty copies. The operator must continually wash the plate to keep it as clean as possible and avoid imperfections upon the copies. The operator must also periodically change the molletons as they wear out.
Additionally, conventional water units require a substantial start-up period of approximately 8-15 minutes. The resulting waste in paper from start-up times, dirty copies, and throw aways is substantial. The time involved in start-ups, changing of molletons, and adjustment of the water unit also is substantial.
To combat the ink-water balance problem, Varn Products Company, Incorporated of Oakland, NJ developed an automatic dampening system called Kompac.COPYRGT.. The Kompac unit utilizes just two rollers; a larger plate form roller, next to a smaller metering roller. The Kompac unit forms a reservoir of special fountain solution in the space called the "nip" between the two rollers. The inward rotating action within the nip mills the solution into the ink, producing extremely fine droplets which are transferred by the plate form roller to the plate. With a squeegee-like action, the plate form roller "splits" the emulsion into components which appropriately coat the image and non-image areas of the plate. A primary feature of the Kompac unit is that any surplus solution is returned to the nip reservoir as the gap between ends of the plate on the plate cylinder passes under the plate form roller.
Both the plate form water roller and metering roller carry ink as picked up from the plate cylinder. This helps ink coverage of the printing press while using less water and ink by allowing the application of a thinner coat of both.
The Kompac unit requires negligible start-up time, allowing the pressman to hang the plate, put the fountain solution into the system, and deliver a sharp clean copy within 45 seconds so that the second or third sheet may be of selling quality. The solution film is automatically adjusted by the image size, requiring the operator to adjust only the ink keys. This thinner film of ink produces less lint hickeys, permits faster drying for quicker turn-around, and higher press speeds without jamming. Significant improvement in quality, productivity and efficiency result without costly waste of time, replacement of molletons and waste of stock.
The Kompac unit is available for use with multiliths such as models 1250 and 1250 LW, and A. B. Dick printing presses Models 350 and 360. However, the Kompac unit cannot be mounted upon presses such as American Type Founders Models Chief 15 and 17, which particularly have problems associated with their standard equipment water units. There is a real and pressing need for the use of the Kompac unit with presses such as the Chief 15 and 17.
It is therefore an object of this invention to provide a mounting means for operably mounting the Kompac automatic dampening system upon American Type Founders Chief 15 and 17 offset printing presses.
It is a further object of this invention to provide a mounting means for water units upon small offset printing presses.
Another object of this invention is to provide a mounting means for water units which is sturdy, economical and easily adapted.
Additional objects, features, and advantages of the invention will become apparent with reference to the accompanying specification and drawings.